(RFE/RL) -- The Presidium of Russia's Supreme Court has ruled that the June 2003 arrest and subsequent pretrial detention of Platon Lebedev, the former head of the financial arm of the Yukos oil company, was illegal.
The surprise decision to "annul" the arrest corresponds to an October 2007 ruling by the European Court of Human Rights, which declared that Lebedev's rights had been violated during his arrest and detention.
The Strasbourg court ordered that Lebedev be compensated in the amount of 10,000 euros ($14,000).
In 2005, Lebedev and his fellow defendant, former Yukos owner Mikhail Khodorkovsky, were convicted of embezzlement and tax-evasion charges and are currently serving eight-year prison sentences. In addition, both men are currently on trial in Moscow on additional embezzlement and money-laundering charges.
The decision will not lead to Lebedev's release in the near future, if at all, defense lawyer Yelena Liptser told RFE/RL, "because, first, he is being held under the new criminal charges and, second, he is serving a sentence according to a court decision. Therefore, naturally, this [decision] cannot affect his custody status."
Russian legal experts are at a loss to explain how the Supreme Court's decision today might affect Lebedev's case.
Vladimir Krasnov, one of Lebedev's lawyers, told RFE/RL that he believes today's decision could, theoretically, mean that entire case against his client is invalidated.
"For example, from July 3 until August 28  the preliminary investigation was carried out. Lebedev was in custody. Now it turns out, illegally," Krasnov said.
"During that time, there were various actions connected with the investigation that he should have -- or had the right to -- participate in. He didn't participate because he was in custody."
He added that he believes the entire case should be sent back to prosecutors.Why Now?
The Supreme Court Presidium today also annulled a 2004 lower-court decision to combine the Khodorkovsky and Lebedev prosecutions into one case.
During the presidium hearing today, Deputy Prosecutor-General Viktor Grin noted that the annulled court rulings were "procedural," and said that the only consequence should be that the individual prosecutors and judges who made them should be reprimanded.
Lebedev himself was brought to the presidium hearing by force, having declared early that he would not attend because he had not been given sufficient time to prepare. Defense lawyers told RFE/RL that they were informed only on December 18 that today's hearing would take place.
Liptser told journalists that today's decision is a "victory" that will enable the defense team to present additional appeals to the upper courts. However, when asked whether the decision would affect Lebedev's 2005 conviction or his current trial, she merely said "we will work on that."
Liptser told RFE/RL she is at a loss to explain why the Supreme Court suddenly decided to rule on this appeal more than two years after the Strasbourg ruling and almost 18 months after the defense team asked for the review.
"Therefore, when the Supreme Court says that they received this decision only now, that is, to put it mildly, not true," she said. "We just don't understand why they decided now to take this ruling into consideration."
Lebedev's lawyers had asked the court to overrule 10 court decisions, but today's ruling annulled only four. The remaining appeals were rejected.
Among the decisions that remain in force was a court ruling that Lebedev and Khodorkovsky serve their prison sentences at a correction facility in the Far Eastern region of Chita.
The European Court of Human Rights has also agreed to hear a joint appeal by Khodorkovsky and Lebedev against their current sentence.
Supporters of the two men claim the cases are politically motivated, part of a Kremlin campaign to punish Khodorkovsky for challenging then-President Vladimir Putin and to increase state control over the vital oil industry.
RFE/RL's Russian Service contributed to this report